In modern motor vehicles, the headrests of at least the front seats are each provided with an actuation unit which serves to move the headrest in the event of an accident into a position in which the vehicle occupant sitting in the seat is protected as much as possible from injuries to the cervical spine. The actuation unit of the headrest is triggered in this process by a triggering device which receives a corresponding signal from an electronic control unit in the event of an accident.
Triggering devices are known from the prior art which use electromagnetic actuation systems with whose assistance the headrest is moved into a predetermined position. Apparatuses of this type have the disadvantage that they react comparatively slowly and that therefore a movement of the headrest in good time is not always ensured on an accident at high speed. In addition, an energy supply is required for the electromagnetic system, which has an unfavorable effect on the required installation space and on the manufacturing costs.
There is a need to provide an actuation unit having a triggering device that is capable of bringing about the desired movement of the headrest as fast and as reliably as possible and can nevertheless be produced as cost-favorably as possible.